This invention relates to filter assemblies, and more particularly, to a filter assembly and a filter element for use in filtering blood or other biological fluids.
In blood oxygenator systems, it is desirable to filter oxygenated blood to remove particulate matter before the blood returns to the patient. In such a system, the filter element should have a high surface area in order to provide adequate blood flow rates and high filtration capacity without clogging. On the other hand, the filter assembly should require only a small amount of blood for priming, since it is desirable to minimize the quantity of blood necessary to prime the oxygenator system. Furthermore, the filter assembly should be constructed so as to minimize the entrapment of air bubbles in the filter. The assembly should also be constructed so as to facilitate removal of debris.
Prior art high surface area filters are disclosed in U.S. Pat. Nos. 1,696,313; 2,330,625; and 3,334,748 and French Pat. No. 1.085.481. Such filters are intended for industrial filtration -- not medical filtration -- and cannot be used for medical filtration inasmuch as they do not provide the combination of features necessary for such use.
It is therefore an object of this invention to provide a filter element and assembly having those features which permit its use as a medical filter that is suitable for use in filtration of blood and other biological fluids.
This and other objects will become apparent from the following description and appended claims.